Jerry Brainum breaks down the pros and cons of intermittent fasting and whether it can fit into a bodybuilding lifestyle.

Intermittent fasting is one of the most popular diet trends of the moment. Perhaps it is even more than a simple trend. The intermittent fasting diet lifestyle has been talked about for nearly a decade at this point and has failed to lose steam. But is it really a more effective way to lose weight? And more importantly for bodybuilders, can it lead to burning away muscle? In our latest episode of Straight Facts, Jerry Brainum goes into detail about the pros and cons of intermittent fasting.

Jerry Brainum has in depth knowledge about many aspects of the diet and nutrition world. He has written countless articles on both in magazine publications and in his Applied Metabolics newsletter. Yet the one he keeps seeing most people asking for is more information about intermittent fasting. That’s how popular this dieting concept has become in modern health and fitness.

Despite Jerry Brainum having already written extensively on the subject – he decided to break down this full explainer video overviewing the pros and cons about intermittent fasting. A definitive recap of his past writings for those who are interested in understanding if this diet is right for them. Let’s jump into it.

What is intermittent fasting?

Jerry Brainum explains that intermittent fasting is short term regular fasting, typically for weight loss but also containing other health benefits. This typically takes the form of fasting for a period of time between 16-48 hours in regular intervals. Not only can this tactic put you into a caloric deficit depending on which intermittent fasting strategy you choose, it’s also designed to speed up your metabolism for the periods of time you do eat food (1).

Types of intermittent fasting

Jerry Brainum details various different intermittent fasting strategies that have gained popularity over the years. Which version an individual decides upon depends on the person’s goal and also what works best for their life schedule and psychological relationship to food and eating.

Here is a quick list of the most common intermittent fasting schedules:

  • 16/8 – This is when you fast for 16 hours and then eat your full meals within an 8 hour period. This is done every day.
  • 2 Day Weekend Fasting – this is when you eat normally Monday through Friday. On the weekend, you limit your calorie intake to 400-500 calories.
  • 24 Hour Fasting – This is when you skip a full 24 hour of eating, once or twice a week.
  • Alternating Fasting – This is when you fast for a full 24 hours, then eat normally for a day, then fast for another 24 hours. This alternates every day of the week.

Does intermittent fasting improve weight loss?

Jerry Brainum also looks into past studies conducted on intermittent fasting and weight loss. Overall, intermittent fasting is seen by the public as a much more successful way to lose weight (2). However, studies have shown that intermittent fasting rarely improves weight loss compared to “traditional” calorie restriction diets.

Despite the fact that there is no scientific weight loss benefit to intermittent fasting, Jerry Brainum points out that it can be a more effective strategy psychologically. Sticking to counting calories every day for, basically, the rest of your life is very challenging for most individuals. Depending on a person’s mindset, intermittent fasting may be an easier way to achieve the same results. Thus leading to less failure scenarios where someone relapses into old eating habits.

Does intermittent fasting lead to muscle loss?

So the biggest question for bodybuilders is whether or not intermittent fasting will lead to burning muscle on top of the fat. Bodybuilders spend the entire year building massive muscle. To lose that in an attempt to cut down and get shredded would be devastating – especially for competitive bodybuilders looking to impress on the stage.

Jerry Brainum understands this concern but ultimately debunks this myth. Intermittent fasting is too short to lead to serious muscle loss. A fasted period would need to last at least 48 hours in order for muscle degradation to occur. The typical intermittent fast usually ranges between 16 and 40 hours at a time, preventing this issue.

However, it should be noted that trying to build muscle while intermittent fasting would be challenging. This is common sense, as usually muscle growth needs a caloric surplus to help build and repair muscle after serious training each day. At best, intermittent fasting should be utilized by bodybuilders during contest prep.

Health benefits of intermittent fasting

While intermittent fasting might only have the slightest advantage for losing weight, it has a more encouraging outlook in terms of improving overall health. Jerry Brainum explains that studies have shown intermittent fasting provides about 95% of the health benefits of traditional calorie restriction. So if intermittent fasting is easier for you than traditional dieting – this might be the perfect solution to improve your overall health.

Jerry Brainum lists through a wide range of health benefits from decreasing high blood pressure (3), preventing certain metabolic conditions, and also helping to potentially prevent certain degenerative diseases such as Alzheimers and dementia (4).

Jerry Brainum also points out that certain studies have found that intermittent fasting helps with easing the downsides of aging. In fact, this is the most key benefit studies have found in an intermittent fasting diet above all else.

Wrap Up

Jerry Brainum goes into extreme detail for just over thirty minutes about nearly every aspect of intermittent fasting. How it can be beneficial for the general public but also how it might intersect with a more hardcore bodybuilding lifestyle. You can watch him go into even more detail than we discuss in this article by watching the latest episode of Straight Facts above. Make sure to stick around every Wednesday for new episodes of Straight Facts starring Jerry Brainum!


  1. Patterson, R.; et al. (2017). “Metabolic Effects of Intermittent Fasting”. (source)
  2. Welton, S.; et al. (2020). “Intermittent fasting and weight loss”. (source)
  3. Erdem, Y.; et al. (2018). “The effect of intermittent fasting on blood pressure variability in patients with newly diagnosed hypertension or prehypertension”. (source)
  4. Zhang, J.; et al. (2017). “Intermittent Fasting Protects against Alzheimer’s Disease Possible through Restoring Aquaporin-4 Polarity”. (source)
Derek Dufour
Derek Dufour has been managing all digital operations on the Generation Iron Network for over six years. He currently manages a team of editors, writers, and designers to provide up-to-date content across the GI Network.